Field of the Invention
The present invention relates to a wireless communication system, and more particularly, to a method of applying a value corresponding to a coverage extension level on the basis of the coverage extension level, and an apparatus supporting the method.
Related Art
3GPP (3rd Generation Partnership Project) LTE (Long Term Evolution) that is an advancement of UMTS (Universal Mobile Telecommunication System) is being introduced with 3GPP release 8. In 3GPP LTE, OFDMA (orthogonal frequency division multiple access) is used for downlink, and SC-FDMA (single carrier-frequency division multiple access) is used for uplink The 3GPP LTE adopts MIMO (multiple input multiple output) having maximum four antennas. Recently, a discussion of 3GPP LTE-A (LTE-Advanced) which is the evolution of the 3GPP L It is in progress.
In recent years, machine-to-machine/Internet of Things (M2M/IoT), which connects all every objects through networks to facilitate obtaining and transmitting necessary information anytime and anywhere, thereby making it possible to offer and use various services, has become a major issue for a next-generation communication market.
While early M2M started with a sensor and an RFID network mainly for local areas, various wired/wireless networks may be used with gradually diversifying purposes and characteristics of applications. Recently, M2M based on a mobile communication network receives growing attention in view of the mobility of objects, a wide range of service areas including not only islands and mountains but also the sea, ease of network management and maintenance, security for reliable data transmission, and guarantee of service quality. Accordingly, with studies on the feasibility of M2M started in 2005, the 3GPP has been conducting a full-scale standardization project under the name “Machine Type Communications (MTC)” since 2008.
The 3GPP regards a machine as an entity that does not require direct human manipulation or intervention and defines MTC as a form of data communication involving one or more of machines. Typical examples of the machine include a smart meter and a vending machine that are equipped with a mobile communication module. Recently, with the introduction of a smart phone that performs communication by automatically connecting to a network, without any user operation or intervention, depending on a user's location or conditions, a mobile terminal having an MTC function is considered as a form of a machine. Also, a gateway-type MTC device connected to an IEEE 802.15 WPAN-based subminiature sensor or RFID is also considered.